Improvement in ox-bow pins



" UNITEn 'STATESw EDWIN N.V EARTWELL, CE SHARON, CONNECTICUT.

IMPROVEMENT IN OX-BOW PINS.

Specification forming part of Letters Patent No. 129,888, dated July 30,18,72.

SPECIFICATION.

`To'ctll whom it may concern.'

Be it known that I, EDWIN N. HARTWELL, of Sharon, Litchfield county,State of Connecticut, have invented certain new and useful Improvementsin Bow-Pins for Ox-Yokes; and I do hereby declare that the following isa full description of the same.

The nature of my invention consists in combining with a washer orbase-plate a perfoi rated stud or pin-holder in which an elastic detentis secured for the purpose bf locking into recesses formed transverselyof the bowpin to prevent its unlocking when inserted into the bow, orgetting lost or separated from the perforated stud when withdrawntherefrom to release the bow from the yoke; but, to describe myinvention more particularly, I will refer to the accompanying drawingforming a part of this specification, the same letters of referencewherever they occur referring y to like parts.

Figure lis a plan view of the bowpin and base-plate, showing the pin inposition for locking the bow into the yoke. Fig. 2 is aplan -view of thesame parts, showing the position of the pin quarter turned round toadmit of its being unlocked from the elastic detent and drawn back torelease the bow from the yoke. Fig. 3 is a longitudinal cut section ofthe same parts through the line fox, Fig 1.

LetterA represents the base-plate or washer, made of malleable iron orother suitable metal, of about three inches in diameter,\with a centralopening of about one and threefourth inch in diameter, or other suitablesize, to admit of the insertion rof the end of the oxbow therein. B Bare screw-holes for securing the plate upon the yoke. At opposite sidesof the upper side ofthe plate are formed,

at the time of casting the plate, or may be otherwise attached thereto,two studs, O and D. The'stud G is intendedas a prop to hold the end ofthe bow-pin E in a horizontal vposition when inserted through the end ofthe bow and has its upper surface slightly hollowe out to prevent anytendency of a side motionV in the end of the pin. The stud D has a horrIizontal circular hole through it, of the diameter "of the bow-pin, withits lower side on a` level with the upper face of the stud C, so as tohold V vthe pin in a horizontal position when inserted into the bow. Inthe lower end ofthe stud D is also formed a vertical slot or opening, F,whichextends up through the stud into the horizontal circular opening.In the upper partof this' slot isv arranged a detent, G, and underneathit a rubber or other suitable elastic material or spring, H, compressedby means of a plate of metal, I, secured by rivets to the under side ofthe base-plate or washer. When thus arranged the elastic force of therubber or spring projects the upper end of the detent constantly againstthe sides of the bow-pin, and into the recesses J and K,cut'transversely in the sides of the bow-pin. The recesses J, at theinner end of the pin, are formed only on opposite sides of the pin, asshown in Figs. 2 and 3. The object of this is to admit of unlocking thepin when necessary to withdraw it from .the bow. This is eifected byturning the head of the pin a quarter way round, as shown in Fig. 2,which brings the parallel sides of the pin in contact with the detent,and thus depresses it so as toallow the pin to draw back to release thebow from the yoke.A In the end of the pin the recess K is annular. Theobject of this is to lock the pin in whatever position it may be in toprevent its getting separated from the stud in which it works. Tofacilitate its being projected forward or shot into the bow the inneredges, as shown at M, Fig. l, are attened or tapered off, s'o that whenpressed in they will readily compress the detentspring and allow the pinto be inserted into the bow and locked therein when turned, as shown inFig. l. Y

Having now described my invention, I will proceed to set forth what Iclaim and desire go secure by Letters Patent of the United tates:

I claim the bow-pin E, made as described, in

Witnesses:

GEORGE A. LAME,

OnAs. F. SEDewICK.

